title: Analysis of high-dose rate brachytherapy dose distribution resemblance in CyberKnife hypofractionated treatment plans of localized prostate cancer.
abstract: The present study is to analyze the CyberKnife hypofractionated dose distribution of localized prostate cancer in terms of high-dose rate (HDR) brachytherapy equivalent doses to assess the degree of HDR brachytherapy resemblance of CyberKnife dose distribution. Thirteen randomly selected localized prostate cancer cases treated using CyberKnife with a dose regimen of 36.25Gy in 5 fractions were considered. HDR equivalent doses were calculated for 30Gy in 3 fractions of HDR brachytherapy regimen. The D5% of the target in the CyberKnife hypofractionation was 41.57 ± 2.41Gy. The corresponding HDR fractionation (3 fractions) equivalent dose was 32.81 ± 1.86Gy. The mean HDR fractionation equivalent dose, D98%, was 27.93 ± 0.84Gy. The V100% of the prostate target was 95.57% ± 3.47%. The V100% of the bladder and the rectum were 717.16 and 79.6mm(3), respectively. Analysis of the HDR equivalent dose of CyberKnife dose distribution indicates a comparable resemblance to HDR dose distribution in the peripheral target doses (D98% to D80%) reported in the literature. However, there is a substantial difference observed in the core high-dose regions especially in D10% and D5%. The dose fall-off within the OAR is also superior in reported HDR dose distribution than the HDR equivalent doses of CyberKnife.
authors.affiliation: Department of Radiotherapy, Apollo Speciality Hospital, Chennai, India. Electronic address: h.sudahar@gmail.com.
authors.forename: H
authors.initials: H
authors.lastname: Sudahar
authors.forename: P G G
authors.initials: PG
authors.lastname: Kurup
authors.forename: V
authors.initials: V
authors.lastname: Murali
authors.forename: P
authors.initials: P
authors.lastname: Mahadev
authors.forename: J
authors.initials: J
authors.lastname: Velmurugan
mesh_terms: D001918:Brachytherapy; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000532:radiotherapy / Q000601:surgery*; D011829:Radiation Dosage; D016634:Radiosurgery; D012189:Retrospective Studies
keywords: CyberKnife; HDR brachytherapy; Hypofractionation; Localized prostate